TAPACHULA, Mexico — The caravan of migrants from Central America grew to roughly 5,000 Sunday, a massive group that stretched along this city’s main highway for more than a half-mile.

They spoke in different accents, fleeing different disasters: joblessness in parts of Honduras, a mounting political crisis in Nicaragua, cities in Guatemala where they were sure their children would languish as they had.

And then there were the deportees. Many of the migrants here had previously lived in the United States, for years or even decades, joining the caravan to reunite with their children, or to resume old jobs. They were undeterred by the American authorities who had apprehended them or the U.S. president who promised to keep them out again.

Some of them had returned voluntarily to their home countries long ago, but eventually determined that there was nothing there for them. Now, they were traversing Mexico while President Trump tweeted about their journey, demanding that the migrants apply for asylum in Mexico before continuing north, threatening to close the U.S. border as Mexican authorities appeared to allow the caravan to proceed.

“It’s time for me to go back to the United States. It’s a country where I can live my life, unlike Guatemala,” said Job Reyes, 36, who had spent most of his childhood and teenage years in Los Angeles, attending kindergarten through high school there.

He said he had returned to Guatemala when his visa expired 14 years ago. He found a job at a call center for Metro PCS, the cellular service provider, where he could make the most of his fluent English. But he earned at most $500 per month. Each time he received a call from a customer, the name of the American city where the client lived flashed on his screen. He searched the names of the cities on the Internet and stared at the monitor.

“When I heard about the caravan, I knew it was my chance,” he said. He called his cousin and uncle in California and told them he was on his way.

Imner Anthony Fuentes, 29, had the same reaction. He had been deported five months ago from Birmingham, Ala. His son was still living there, with his U.S. citizen girlfriend, not far from the framing store where Fuentes had worked for six years. He was used to the back-and-forth: He said he had been deported six times.

“That’s just how it is,” Fuentes said. “They catch you, and you try to get back.”

Juan Jimenez, 32, said he was deported back to Honduras six months ago from Phoenix, where he worked for a wood-flooring business. He was on his way to see his 6-year-old son, still living in Arizona.

“I miss him,” he said.

Honduran migrants walk in a caravan heading to the United States on the road linking Ciudad Hidalgo and Tapachula, Chiapas state, Mexico, on Sunday. (Pedro Pardo/AFP/Getty Images)

Evin Mata, 21, said he was deported three months ago from Fort Lauderdale, Fla., where he worked in construction not far from the city’s airport.

“We are workers. What are we supposed to do in Honduras if there’s no work?” he said.

Some members of the caravan plan to apply for political asylum, citing the threats they’ve received from gangs in Honduras or, in Nicaragua, the government’s assaults on the political opposition. But as the group grew larger, it also grew more varied, and it appeared that most of the migrants were not planning to apply for asylum.

“We believe there are at least 5,600 now, and we expect more to join us,” said Rodrigo Aveja, one of the group’s organizers.

The deportees and returnees were clear about their intentions to cross the border illegally, hoping to slip between patrol officers.

“It’s the only way,” said Nestor Reyes, 34, whose son was with his wife in Columbus, Ohio. He’d been calling her periodically on the journey to check in.

On Sunday afternoon, Trump wrote on Twitter that the United States would turn migrants away if they don’t apply for asylum in Mexico.

The vast majority of the caravan’s members have refused to apply for refuge in Mexico, worried that the process could lead to their detention or deportation. So far, Mexican police have backed down, allowing the migrants to continue without applying for documentation.

A Honduran migrant is comforted by a Mexican paramedic after her mother fainted while crossing the border between Guatemala and Mexico, in Ciudad Hidalgo, Mexico, on Saturday. (Oliver De Ros/AP)

At one Mexican police checkpoint, Nestor Reyes slipped by as the police chief was addressing the caravan.

“I’m not stopping for that,” he said.

For the deportees, the caravan offers safe passage through parts of Mexico where gangs and cartels typically have free rein. If not for the protection of the large group, they would have to pay thousands of dollars for a smuggler.

But the journey’s last step, crossing the border into the United States, is something they ­haven’t planned yet, although their previous attempts offer some guidance.

“It’s easier through the desert than the river,” Fuentes said.

He had run into other deportees in the caravan, men from different parts of Central America who once worked in different parts of the United States. Some traded fragments of the English they had learned. They talked about what they remembered from their time across the border.

They described how they were deported — traffic tickets that led to detention, workplace raids, expired visas. They each had theories about what Trump might do to reinforce the border, but even when they discussed the most extreme rumors, they were undeterred.

“I heard he’s sending the military to the border,” said Job Reyes. “I heard they could shoot at us.”

On his shoulders, he carried a small boy whom he had met a few days earlier and who was having trouble walking.

“I don’t know what they expect about us,” he said, “but basically what we want is to have a better opportunity, to have a job, you know?”

A migrant walks off the shore on the Mexican side of the Suchiate River after wading across, on the border between Guatemala and Mexico, in Ciudad Hidalgo, Mexico, on Saturday. (Moises Castillo/AP)